The invention relates to a magnetic-tape-cassette apparatus having tape-guide means for a magnetic tape at the location of the head gaps of a magnetic head of the apparatus, comprising tape-guide elements which guide the magnetic tape relative to the magnetic head and the head gaps thereof, a first pair of tape-guide elements and a second pair of tape guide elements being provided at opposite sides of the magnetic head. The first pair of tape-guide elements are disposed directly adjacent the magnetic head, the second pair of tape-guide elements are disposed further outward and are spaced at a distance from the magnetic head and the tape-guide element adjacent this magnetic head. Each of the tape-guide elements are fork-shaped and have guide limbs which bound the transport path of the magnetic tape.
Such tape-guide means for a magnetic tape at the location of the head gaps of a magnetic head of a magnetic-tape-cassette apparatus are known from U.S. Pat. No. 5,202,808. Said means comprise an injection-moulded plastics part comprising a holder for a magnetic head and inner tape guide elements disposed directly adjacent the head face of the magnetic head at both sides of this head face, viewed in the transport direction. Said injection-moulded plastics part also comprises further outer tape guide elements, which are spaced from the inner tape-guide elements on the magnetic head and which ensure that the magnetic tape is guided over a greater length at both sides of the magnetic head.
The individual tape-guide elements are fork-shaped and accordingly they have guide limbs along which the tape can run. One guide limb of each of the tape-guide elements has a reference or contact face which extends vertically in relation to the tape-transport path, the contact face of the other guide limb being outwardly inclined relative to the transport path. All the contact faces of the tape-guide elements are adjusted in such a way that an edge of the magnetic tape, as it moves past the elements, is in contact with all the vertical contact faces when the adjustment of the head is correct.
U.S. Pat. No. 3,756,610 describes a magnetic-tape guide arrangement which also comprises pairs of guide elements. These pairs of guide elements are arranged at a distance at opposite sides of the magnetic head. Each pair of tape-guide elements has a sub-element with a guide edge past which the magnetic tape moves with one of its longitudinal edges, and a sub-element with a guide edge past which the magnetic tape moves with its other longitudinal edge. The distance of the guide edges in a direction transverse to the tape transport direction is B.sub.min. This is the minimum tape width in compliance with the standard. For all tape widths larger than B.sub.min the magnetic tape is kinked at the edges between the closely spaced sub-elements of a pair of tape-guide elements owing to a sharp offset of the guide path. As a result, the magnetic-tape edges are subject to considerable wear.
From U.S. Pat. No. 5,134,536 it is known to construct all the tape-guide elements and a holder for the magnetic head as a single injection-molded part. However, the method of guiding the tape is different from that of the instant invention, described below, and leads to different operating results.